Air filter



FIG. 1 is a front perspective view of one embodiment of the air filter, in accordance with the design;

FIG. 2 is a front elevational view of the air filter of FIG. 1;

FIG. 3 is distal end elevational view of the air filter of FIG. 1;

FIG. 4 is a proximal end elevational view of the air filter of FIG. 1;

FIG. 5 is bottom view of the air filter of FIG. 1;

FIG. 6 is a top view of the air filter of FIG. 1;

FIG. 7 is another front perspective view of the air filter of FIG. 1, positioned partway into a cabinet for housing the AIR FILTER, the cabinet being depicted in broken lines as environment;

FIG. 8 is a front perspective view of another embodiment of the air filter, in accordance with the design; and,

FIG. 9 is a front perspective view of still another embodiment of the air filter, in accordance with the design.

The broken lines on the surface in the drawings show portions of the air filter that form no part of the claim. The portions of a cabinet for the air filter shown in FIG. 7 are shown as environment only and do not form part of the design. The drawings are shaded to indicate contrasting surfaces, with the shaded portions being stippled. 

CLAIM The ornamental design for an air filter, as shown and described. 